The buckwheat hulls allow air to circulate throughout the pillow. Cooling it off quickly * Filled with 100% buckwheat hulls that shape themselves to your head and neck * Will conform and adjust perfectly to your head, neck, and spine. Will not collapse like foam * Hypo-allergenic for people sensitive to foam and feather allergies * Hulls have properties that make them uniquely comfortable, supportive and therapeutic for a restful night sleep